Models of the entire or particular regions or systems of the human anatomy are commonly employed in the general education and training of medical personnel as well as specialized training of specialists, surgeons, surgical staff, and other medical personnel in performance of specialized diagnostic, therapeutic, and surgical procedures. See, for example U.S. Pat. Nos. 4,439,164, 5,104,328, 5,356,295, 5,951,301, 6,062,866, 6,234,804, 6,267,599, 6,336,812, 6,474,993, 6,568,941, 6,780,016, and 6,908,309. Neonatal models of the developing fetus are provided to educate and inform prospective parents as disclosed in the above-referenced '295 and '328 patents. Models of the thoracic region and cardiovascular system are provided to educate cardiologists and surgeons as disclosed in the above-referenced '804, '599, '866, and '016 patents. In the above-referenced '941 patent, tactilely realistic, soft and pliant, models of the female breast encasing hard internal lesion models, and that may be transparent at least in part, are disclosed for needle biopsy training. A dynamic and accurate anatomical model of skin, muscle, bone, and ligaments of the human knee with a “true-to-life” feel is provided as the “Hillway Knee” by Hillway Surgical Ltd., Chichester UK, for simulated arthroscopic and open training procedures and to teach patients about to undergo knee surgery. A wide variety of simulations of regions and systems of the human body are disclosed in the above-referenced '812 patent. A housing is provided and multiple simulations of normal and abnormal internal organs and tissues of a body region of various degrees of complexity are provided to be selectively placed in the housing for training a surgeon, particularly in performing laparascopic procedures performed through the housing.
It is necessary to train surgeons and urologists in performing certain surgical procedures in the abdominopelvic region of the human body, e.g., procedures for treating incontinence or diagnosing and treating various conditions or diseases of the male prostate. For example, surgeons and urologists are trained to apply penetrating needles through the skin in the urogenital triangle of the male perineum between the lower genital area, behind the scrotum, and the location of the anus. The 3-dimensional perineum is the region below the pelvic cavity situated within the pelvic outlet bordered by the symphysis pubis, the ischiopubic rami, the ischial tuberosities, the sacrotuberus ligaments, and the coccyx. The needle is advanced through the underlying muscle layers and perineal space avoiding arteries to dispose the needle distal tip near or in the prostate. Such needles are then used to perform a prostate tissue biopsy or surgical excision or to deliver a treatment, e.g., brachytherapy. Surgeons or urologists typically palpate the tissue in the perineum through the skin and the prostate through the anus to identify an insertion path that is likely to dispose the needle distal tip at the desired site.
With respect to the application of brachytherapy to treat early stage prostate cancer, radioactive pellets or seeds of, for example, iodine-125, palladium-103, or iridium-192, are deposited directly into the prostate through a brachytherapy needle passed through the perineum as generally described above. In this procedure, it is desirable to deposit the radioactive seeds at precise locations of the cancerous tumors so that radiation is administered directly to the tumors with less damage to surrounding tissues. A substantially higher radiation dosage can be to the prostate than to the surrounding tissues, as compared to external beam radiation therapy. The procedure need only be performed once, and impotence and urinary incontinence complications are significantly reduced, as compared to radical prostate surgery procedures.
Imaging techniques, such as transrectal ultrasound, CT scans, or MRI, are used to accurately guide placement of the biopsy needle distal tip and the brachytherapy needle distal tip into the cancerous tumors and to a desired depth. The junction of the base of the prostate and the bladder provides a common reference plane for guiding such needle insertion. Identifying this critical reference “base” plane is critical to proper needle and seed placement.
One previously known technique for imaging the base plane is to visualize the plane in either transverse or sagittal ultrasound imaging. Ultrasound imaging is enhanced by injection of contrast agent comprising aerated K-Y jelly and water through a catheter into the patient's bladder. A catheter, e.g., a standard Foley catheter, may be inserted into the patient's urethra disposing the catheter lumen distal port proximal of the junction with the bladder. The contrast agent is then injected through the catheter lumen and the urethra. The agent moves distally towards the patient's bladder and is visible to an ultrasound probe, positioned in the patient's rectum, thereby facilitating imaging. The imaged urethra provides guidance in the advancement of the biopsy or brachytherapy needle distal tip to precise locations in the prostate.
Thus, the surgeon or urologist must gain expertise in judging the direction and depth of needle advancement in these procedures using the available tools that do not provide precise visual or tactile determination of the biopsy or brachytherapy sites in the prostate. In virtually all fields of surgery, surgical training on cadavers is required before surgeons are permitted to perform their first patient procedure. However, cadavers are not readily available for such training. It is not possible to visualize the advancement of the needle tip within the cadaver body, and it is not possible to assess whether damage has been done to internal organs, vessels, and nerves in the abdominopelvic region without destructive autopsy at the site. Such an autopsy renders the cadaver unusable for repeat training.
Similar problems are encountered in training to perform other procedures involving blindly advancing a needle or other elongated medical instrument around the internal organs and alongside bones, nerves, and blood vessels to effect other treatments and implantations of implantable medical devices in the abdominopelvic region.
Consequently, it would be desirable to provide a realistic anatomic model of the abdominopelvic region to demonstrate and facilitate training in the performance of these procedures and educating the patient about a procedure. Moreover, it would be desirable to provide such an anatomic model to facilitate demonstration of improved needles and other elongated medical instruments intended to access the tissues, spaces and structures within the abdominopelvic region.